Patent GB-971704-A (GB)
Title: 6-substituted dihydroquinolines and rubber compositions containing the same
IPC: C08K5/3437
Filed: 1961-05-26
Abstract: The invention comprises 6 substituted 1, 2-dihydroquinolines of the general formula <FORM:0971704/C1/1> wherein x is 1, 2 or 3; R is a C2- 8 alkylene group; R1 and R2 are C1- 4 alkyl groups; Y is R3O or R4R5N; R3 is C1- 6 alkyl, phenyl, alkyl phenyl, or cyclohexyl group and R4 and R5 are C1- 4 alkyl groups, which may be prepared by reacting a p.-substituted aniline <FORM:0971704/C1/2> with a C1- 4 alkyl methyl ketone in the presence of a dehydrating catalyst. Suitable ketones are acetone, methyl ethyl ketone, methyl isopropyl ketone and methyl isobutyl ketone, while suitable p.-substituents for the aniline are methoxyethoxy, ethoxyethoxy, butoxyethoxy, hexoxyethoxy, phenoxyethoxy, methoxyethoxyethoxy, ethoxyethoxyethoxy, butoxyethoxyethoxy, ethoxyethoxyethoxyethoxy, hexoxyethoxyethoxy, methoxyisopropoxy, methoxyisopropoxyisopropoxy, methoxyisopropoxyisopropoxyisopropoxy, phenoxyisopropoxy, p-sec.-butylphenoxyethoxy, p-tert.-phenoxyethoxy, b .-diethylaminoethoxyethoxy, b -diethylaminoethoxy, dimethylaminoisopropoxy, g  dimethylamino-n-propoxy, b -dibutylaminoethoxy, g  phenoxy-n-propoxy, g  cyclohexoxy-n-propoxy, d  methoxy-n-butoxy, e -methoxy-n-amyloxy, o -methoxy-n-hexoxy, o -methoxy-n-heptoxy, and o -methoxy-n-octoxy groups.  Catalysts specified are iodine and aromatic monosulphonic acids such as benzene and toluene sulphonic acids.  The products are antioxidizing agents for rubber (see Division C3).  The substituted anilines may be prepared from p-nitrophenol by reacting with the alkali metal phenate with a dihalo alkane to give a p-nitrophenoxy alkyl halide which is reacted with an alcohol, cyclohexanol, phenol or dialkylamine and then reduced; or by reacting p-nitrochlorobenzene with an ether alcohol and reducing the product.  Examples describe the reaction of acetone with 1 (4-amino-phenoxy)-2-n-butoxy ethane, diethylene glycol methyl (4-aminophenol) ether and para-(diethylaminoethoxy) aniline.ALSO:Degradation of rubbers by ozone, heat, ageing and oxidation is inhibited by compounds of the formula <FORM:0971704/C3/1> wherein x is 1, 2 or 3; R is a C2- 8 alkylene group; R1 and R2 are C1- 4 alkyl groups; Y is R3O-or R4R5N-, R3 is C1- 6 alkyl phenyl, alkyl phenyl or cyclohexyl groups; R4 and R5 are C1- 4 alkyl groups.  Suitable Y substituents are methoxyethoxy, ethoxyethoxy, butoxyethoxy, hexoxyethoxy, phenoxyethoxy, methoxyethoxyethoxy, ethoxyethoxyethoxy, butoxyethoxyethoxy, ethoxyethoxyethoxyethoxy, hexoxyethoxyethoxy, methoxyisopropoxy, methoxy-isopropoxy, methoxyisopropoxyisopropoxy, methoxy-isopropoxyisopropoxyisopropoxy, phenoxy-isopropoxy, p.-sec butylphenoxyethoxy, p-tert.-butylphenoxyethoxy, b di-ethylaminoethoxyethoxy, b -diethylaminoethoxy, dimethylaminoisopropoxy, g -dimethylamino-n-propoxy, b -dibutyl-aminoethoxy, g -phenoxy-n-propoxy, g -cyclohexoxy-n-propoxy, o -methoxy-n-hexoxy, e -methoxy-n-amyloxy, o -methoxy-n-heptoxy and o -methoxy-n-octoxy. Examples describe the use of these compounds in conventional rubber compositions containing crushed sheet rubber, crepe rubber and styrene-butadiene rubber which may be vulcanized.